FWH-70A Equivalent & Substitute Parts

Part Overview

The FWH-70A is a 70A cartridge fuse manufactured by Eaton - Bussmann Electrical Division, rated for 500 VAC and 500 VDC operation with bolt mount configuration. This component is designed for electrical and industrial applications requiring high breaking capacity (200kA AC, 50kA DC) and is currently in active production status. Substitute parts are identified when equivalent electrical ratings, mechanical compatibility, and regulatory approvals align with the original specification.

Substiute Parts

FWH-70A

Eaton - Bussmann Electrical DivisionIn Stock: 963FWH-70A Datasheet

Current PartRFQ

L50S070.T

Littelfuse Inc.In Stock: 947L50S070.T Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the FWH-70A is determined by the following critical parameters:

• Current Rating: Must be 70A
• Voltage Rating - AC: Must be 500 VAC minimum
• Voltage Rating - DC: Must be 500 VDC or higher
• Mounting Type: Must be Bolt Mount
• Fuse Type: Must be Cartridge
• Package / Case: Must be Cylindrical with Blade Terminal (Bolt)
• Approval Agency: Must include CE, CSA, and UR certifications
• RoHS Compliance: Must be RoHS Compliant or equivalent

The L50S070.T meets the current rating, AC voltage, mounting type, fuse type, package configuration, and regulatory approvals. However, the DC voltage rating is 450 VDC, which is below the 500 VDC specification of the FWH-70A. This represents a voltage derating in the DC application space.

Parameter Comparison

Engineering Selection Recommendations

The L50S070.T is electrically and mechanically compatible with the FWH-70A for AC applications at 500 VAC. Both components carry identical regulatory approvals (CE, CSA, UR) and meet RoHS compliance requirements.

For DC applications, the L50S070.T operates at a reduced voltage rating of 450 VDC compared to the FWH-70A specification of 500 VDC. Additionally, the breaking capacity at rated DC voltage is reduced from 50kA to 20kA. These deratings must be evaluated against the actual system requirements before selection.

The L50S070.T is specified as Fast Blow response, whereas the FWH-70A response time is not provided in the available data. This difference may affect circuit protection characteristics in time-sensitive applications.

Frequently Asked Questions (FAQ)

Q: Can the L50S070.T directly replace the FWH-70A in all applications?

A: Direct replacement is valid for AC applications at 500 VAC. For DC applications, the reduced voltage rating (450 VDC vs. 500 VDC) and reduced breaking capacity (20kA vs. 50kA) must be verified against system requirements.

Q: What is the significance of the voltage derating in the L50S070.T?

A: The L50S070.T is rated for 450 VDC maximum, which is 50 volts below the FWH-70A specification. This component cannot be used in circuits where the DC voltage exceeds 450 volts.

Q: Are the regulatory approvals equivalent between these two parts?

A: Yes. Both the FWH-70A and L50S070.T carry CE, CSA, and UR certifications, indicating equivalent regulatory compliance for their respective rated specifications.

Q: What does "Fast Blow" response mean for the L50S070.T?

A: Fast Blow indicates rapid fuse element melting in response to overcurrent conditions. This characteristic affects the speed of circuit protection and should be verified as compatible with the intended application.

Q: Are there packaging differences between these components?

A: Both components use cylindrical cartridge design with blade terminal (bolt) mounting. The L50S070.T dimensions are specified as 1.000" Dia x 2.126" L (25.40mm x 54.00mm). Physical dimensions of the FWH-70A are not provided in the available data.

Q: What is the difference in breaking capacity between these parts?

A: At rated AC voltage (500 VAC), both parts have identical breaking capacity of 200kA. At rated DC voltage, the FWH-70A provides 50kA breaking capacity while the L50S070.T provides 20kA, representing a 60% reduction in DC fault current handling capability.